| <!-- $Id$ --> |
| <!-- |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You under the Apache License, Version 2.0 |
| (the "License"); you may not use this file except in compliance with |
| the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| --> |
| <body> |
| <p> |
| Commons-Collections contains implementations, enhancements and utilities |
| that complement the Java Collections Framework. |
| </p> |
| <p> |
| The Apache Jakarta Commons Collections Framework component adds a significant |
| amount of enhancements to the standard JDK collections. These enhancements |
| come in the form of new interfaces, new implementations and utility classes. |
| </p> |
| <p> |
| See also the <code>java.util</code> package for the standard Java collections. |
| </p> |
| |
| <h4>Main features</h4> |
| <p> |
| Commons-Collections defines a number of key interfaces: |
| </p> |
| <table border="1" cellspacing="0" cellpadding="3"> |
| <tr bgcolor="#CCCCFF" class="TableHeadingColor"> |
| <th>Interface</th><th>Description</th> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.Bag} |
| </td> |
| <td valign="top"> |
| A new <code>Collection</code> subinterface that stores each object together |
| with the number of occurances. Methods are provided to get the number of |
| occurances, and to add and remove a certain number of that object. |
| </td> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.Buffer} |
| </td> |
| <td valign="top"> |
| A new <code>Collection</code> subinterface that allows objects to be removed |
| in some well-defined order. Methods enable the next item to be peeked and removed. |
| </td> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.BidiMap} |
| </td> |
| <td valign="top"> |
| A new <code>Map</code> subinterface that allows lookup from key to value and |
| from value to key with equal ease. |
| </td> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.OrderedMap} |
| </td> |
| <td valign="top"> |
| A new <code>Map</code> subinterface that is used when a map has an order, but is |
| not sorted. Methods enable bidriectional iteration through the map. |
| </td> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.MapIterator} |
| </td> |
| <td valign="top"> |
| A new <code>Iterator</code> subinterface specially designed for maps. This iterator |
| avoids the need for entrySet iteration of a map, and is simpler to use. |
| </td> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.ResettableIterator} |
| </td> |
| <td valign="top"> |
| A new <code>Iterator</code> subinterface that allows the iteration to be reset back |
| to the start. Many iterators in this library have this functionality. |
| </td> |
| </tr> |
| <tr> |
| <td> |
| {@link org.apache.commons.collections.Closure}<br /> |
| {@link org.apache.commons.collections.Predicate}<br /> |
| {@link org.apache.commons.collections.Transformer}<br /> |
| {@link org.apache.commons.collections.Factory}<br /> |
| </td> |
| <td valign="top"> |
| A group of <i>functor</i> interfaces that provide plugin behaviour to various |
| collections and utilities. |
| </td> |
| </tr> |
| </table> |
| <p> |
| In addition to the interfaces, there are many implementations. |
| Consult each subpackage for full details of these. |
| </p> |
| |
| </body> |
